1. Field of the Invention
The invention relates to a method and a device for the adsorption or chemisorption of gaseous materials from a raw gas stream by addition of dry adsorbents or by adsorbents possibly with properties, which effect a chemical reaction with the adsorbed gas components. The raw gas and the fresh adsorbent are fed to a separator structure including several filter chambers formed as bag filter collectors. A dust return is performed with a recirculation of the 20- to 80-fold of the employed fresh adsorbent. A part of the gas is maintained in circulation in the bag filter collector by way of a trap shaft or central guide pipe with a coordinated nozzle. Thereby separated dust is participating after its purification in the recirculation process.
Such a method is to increase the yield for the adsorbent in case of drying processes with the lowest possible investment requirement and under avoidance of complicated and expensive equipment for the return of the dust. This method and a device for the performance of the method are described in the German Printed Patent Documents DE-OS 38 01 913 and DE-OS 38 06 862. This method and device serve for the adsorption and chemisorption, respectively, of gaseous materials from a gas stream. It is a substantial feature of the method that the dust is retained and is returned within a fabric filter, and this is achieved by disposing a combination, comprising a nozzle and a trap shaft, in the lower part of the fabric filter, whereby both a changeable and adaptable gas return as well as a dust return changeable and adaptable within wide ranges are effected.
Both the method as well as the device allow recognition of disadvantages which are recited in the following in more detail by reference with respect to the state of the art.
Various other attempts have been taught in connection with gas purification such as for example in the following references:
European Patent Application 0,318,934 to Szymznski et al.,
U.S. Pat. No. 3,424,501 to H. T. Young,
U.S. Pat. No. 3,520,109 to E. K. Caskey,
U.S. Pat. No. 3,704,573 to Koller et al.,
U.S. Pat. No. 3,839,185 to Vicard,
U.S. Pat. No. 3,926,595 to Bockman,
U.S. Pat. No. 4,432,862 to Swart et al.,
U.S. Pat. No. 4,865,627 to Dewitz et al.,
U.S. Pat. No. 4,913,815 to Shulda, and
U.S. Pat. No. 4,999,032 to Wright.